Four long, parallel conductors carry equal currents of I = 5.00 A. The direction of the current is into the page at points A and B (indicated by the crosses) and out of the page at C and D (indicated by the dots). Calculate the magnitude and direction of the magnetic field at point P, located at the center of the square with an edge length 0.200 m.

Explanation:

The magnetic field due to a straight wire carrying current is given by

B = μo• I / 2πr

Where,

μo = permeability of free space

μo = 4π×10^-7 Tm/A

I is the current in wire

I = 5A

r Is the distance of point from the wire.

The distance between the parallel conductors and the point is r/2

R = 0.283/2 = 0.1415m

Check attachment on how I used Pythagoras theorem to find the diagonal of the square..

Hence, the magnetic field at point P is

B = μo•I / 2πR

B = 4π × 10^-7 × 5 / 2π × 0.1415

B = 7.07 × 10^-6 T.